Mass and capacity - Add and subtract capacity - Presentation

In the lesson on mass and capacity, students are introduced to the concepts of adding and subtracting volumes, specifically in millilitres and litres. The lesson begins with a review question to solidify the students' understanding of the relationship between millilitres and litres. The main activities involve practical exercises where students use Base Ten blocks and place value charts to add and subtract different volumes of liquid. For example, Zach demonstrates how to add 3 litres and 500 millilitres to 3 litres and 300 millilitres. Students are then encouraged to apply the same approach to similar problems, such as combining 4 litres and 600 millilitres with 2 litres and 100 millilitres, or subtracting smaller volumes like 800 millilitres from 375 millilitres.

Further activities include real-life scenarios, such as calculating the total volume of ingredients needed to make a Summer Punch for two people. Students discuss different methods to add up the volumes of pineapple juice, orange juice, and lemonade required for the recipe. They also consider how much of each ingredient would be needed to serve four people and whether two 500 millilitre bottles of lemonade would suffice. In another activity, students are presented with a café scenario where they must track the milk used for each order, starting with a certain amount and subtracting the volumes used to find out how much is left. These exercises not only teach students how to work with capacity but also how to apply mathematical reasoning to everyday situations.